Technical Abstract:
The lesser grain borer, Rhyzopertha dominica, is a major insect pest of stored grains, including rough rice. Diatomaceous earth (DE) is a natural inert dust that can be used to control stored-grain beetles, however, R. dominica is more tolerant to DE compared to other beetle species. Mortality of adult R. dominica exposed on rough rice treated with the label rate of a commercial DE product did not exceed 59% even when used at the label rate. In addition, the extensive survival led to progeny production and damaged kernels. When the insect growth regulator (IGR) methoprene was combined with DE, progeny production was eliminated. Results show that combination treatments of DE plus methoprene could be used to control R. dominica in stored rough rice.